Electrically gauged N=4 supergravities in D=4 with N=2 vacua

TL;DR

This paper classifies and constructs N=2 vacua in electrically gauged N=4 supergravity in four dimensions, revealing their spectrum, gauge groups, and low-energy effective action structure.

Contribution

It provides a systematic algebraic classification of N=2 vacua in N=4 supergravity and explicitly constructs a special class of solutions with detailed properties.

Findings

Spectrum forms N=2 supermultiplets

Unbroken gauge groups depend on vector multiplet count

Effective action determined by special Kahler geometry

Abstract

We study N=2 vacua in spontaneously broken N=4 electrically gauged supergravities in four space-time dimensions. We argue that the classification of all such solutions amounts to solving a system of purely algebraic equations. We then explicitly construct a special class of consistent N=2 solutions and study their properties. In particular we find that the spectrum assembles in N=2 massless or BPS supermultiplets. We show that (modulo U(1) factors) arbitrary unbroken gauge groups can be realized provided that the number of N=4 vector multiplets is large enough. Below the scale of partial supersymmetry breaking we calculate the relevant terms of the low-energy effective action and argue that the special Kahler manifold for vector multiplets is completely determined, up to its dimension, and lies in the unique series of special Kahler product manifolds.